The blood brain barrier is effective against quizlet

The blood vessels that vascularize the central nervous system (CNS) possess unique properties, termed the blood–brain barrier, which allow these vessels to tightly regulate the movement of ions, molecules, and cells between the blood and the brain. This precise control of CNS homeostasis allows for proper neuronal function and also protects ...

The blood–brain barrier usually allows small molecules to penetrate the brain but not larger molecules such as neurotransmitters. Most neurotransmitter precursors are amino acids that can be actively transported into the brain via the carrier system of capillary endothelial cells, which can transport substances from the blood to endothelial ...Functions of the BBB. - Protects the brain from "foreign substances" (xenobiotics) in the blood that may injure the brain. - Protects the brain from hormones and …Blood Brain Barrier (BBB) Prevents circulating blood substances (bacteria and fungi) from reaching the CSF. Consists of: tight junctions between non-porous endothelial cells, basement membrane, astrocyte processes. Glucose and amino acids cross slowly by carrier mediated transport mechanism. Features of Brain Microvessels.The blood-brain barrier (BBB) is a diffusion barrier, which impedes influx of most compounds from blood to brain. Three cellular elements of the brain microvasculature compose the BBB-endothelial cells, astrocyte end-feet, and pericytes (PCs). Tight junctions (TJs), present between the cerebral endothelial cells, form a diffusion barrier, which ... The blood-brain barrier is usually effective at keeping foreign or toxic substances out of your central nervous system. Most of the time this is a good thing, but it can pose a problem when developing new drugs for the nervous system.3) The blood-brain barrier is effective against the passage of: 3) _____ A) nutrients such as glucose B) metabolic waste such as urea C) water D) anesthetics E) alcohol B 4) The sympathetic and parasympathetic nervous systems are subdivisions of the: 4) _______ A) autonomic nervous system B) voluntary nervous system C) somatic nervous system D ...Sensory input and mental activity. Theta waves. Emotional stress waves. Delta waves. Deep sleep waves in adults. Cranial nerves. Nerves that come off the brain. Study with Quizlet and memorize flashcards containing terms like Cerebrum, cerebellum, brainstem, and diencephalon, Skull and connective tissues, Blood brain barrier and more.

Function: regulates the diffusion of metabolites and metabolic. products between blood and brain to maintain the physiological composition of the CNS microenvironment. This barrier transports substances that the brain consumes rapidly (e.g. glucose, amino acids, lactate and ribonucloesides). Malignant primary brain tumors, secondary brain ...Abstract. The blood-brain barrier (BBB) provides significant protection against microbial invasion of the brain. However, the BBB is not impenetrable, and mechanisms by which viruses breach it are becoming clearer. In vivo and in vitro model systems are enabling identification of host and viral factors contributing to breakdown of the unique ...The blood-brain barrier is effective against which of the fo | Quizlet Related questions with answers Which of the following is not a function of CSF? A. To regulate the chemical environment of the nervous tissue B. To rinse metabolic wastes from the nervous tissue C. To provide oxygen and nutrients to the nervous tissue D.Inhibition of the interaction between the scaffolding protein PSD-95 and the NMDA receptor has been shown to obstruct ischemic stroke-triggered excitotoxic reactions, leading to neuronal death. The peptides NR2B9c and N-dimer are inhibitors of this interaction. Delivery of the peptides to the brain is challenging due to the general low …Study with Quizlet and memorize flashcards containing terms like Voluntary muscle control is one of functions of the A) cerebellum. B) cerebrum. C) spinal cord. D) brain stem. E) meninges., Functions of the meninges include A) support for the brain and spinal cord. B) transmission of signals from the peripheral nervous system. C) protection from external …May 3, 2023 · Temozolomide, the current chemotherapy used for glioblastoma, does cross the blood-brain barrier, but is a weak drug, Sonabend said. The blood-brain barrier is a microscopic structure that shields the brain from the vast majority of circulating drugs. As a result, the repertoire of drugs that can be used to treat brain diseases is very limited. maintains the constancy of the brain's internal environment protects the neural tissue from variations in blood composition and toxins many of these molecules regulate neuronal excitability, a similar change in the composition of interstitial uid in the central nervous system (CNS) can lead to uncontrolled brain activity

To retain optimal function, the brain and the rest of the body needs a steady supply of glucose or ‘blood sugar’ to maintain concentration and mood. Try our Symptom Checker Got any other symptoms? Try our Symptom Checker Got any other sympt...Study with Quizlet and memorize flashcards containing terms like Psychopharmacology includes the study of: A. Blood Pressure medicine B. Drugs of abuse C. Ulcer medications D. Psychoactive drugs and drugs of abuse, Pharmacokinetics include: A. Absorption B. Distribution C. Absorption, Distribution, Metabolism, and excretion D. Metabolism and …barrier [bar´e-er] 1. an obstruction. 2. a partition between two fluid compartments in the body. 3. a covering used to prevent contact with body fluids. alveolar-capillary barrier (alveolocapillary barrier) see under membrane. blood-air barrier alveolocapillary membrane. blood-aqueous barrier the physiologic mechanism that prevents exchange …Lack of oxygen in the brain will cause permanent brain damage in as little as four minutes. Another four to six minutes without the brain receiving blood will result in increased brain damage, coma and then death.

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The blood-brain barrier is usually effective at keeping foreign or toxic substances out of your central nervous system. Most of the time this is a good thing, but …Why do we need the BBB? - The brain lacks the type of immune system present in the rest of the body. - Neurons cannot be replicated and replaced, the barrier is in place to …The blood-brain barrier (BBB), a dynamic interface between blood and brain constituted mainly by endothelial cells of brain microvessels, robustly restricts the entry of potentially harmful blood-sourced substances and cells into the brain, however, many therapeutically active agents concurrently cannot gain access into the brain at effective do...The blood-brain barrier is effective against the passage of: A) nutrients such as glucose B) metabolic waste such as urea C) water D) anesthetics E) alcohol A The sympathetic and parasympathetic nervous systems are subdivisions of the: A) autonomic nervous system B) voluntary nervous system C) somatic nervous system D) central nervous system E ...In the development of central nervous system (CNS) drugs, the blood-brain barrier (BBB) restricts many drugs from entering the brain to exert therapeutic effects. Although many novel delivery methods of large molecule drugs have been designed to assist transport, small molecule drugs account for the vast majority of the CNS drugs …

The two major divisions of the nervous system are the. PNS and the CNS. All behavior is the product of. an organism's genetic endowment. an organism's experience. an organism's perception of the current situation. Proteins that bind to DNA and influence the rate at which particular structural genes will be expressed are called. Apr 6, 2017 · One possible way around the problem is to “trick” the blood–brain barrier into allowing passage of the drug. This is the so-called Trojan horse approach, in which the drug is fused to a ... it is a set of characteristics within the vessels and cells that prevent certain substances from entering the brain. These are the least permeable capillaries of the body. These excludes many potential harmful substances. They are useless against some substances. True or false. The BBB is a physical structure.To recreate the barrier, the research team took those cell types that naturally make up the blood-brain barrier—microvascular endothelial cells, human astrocytes and human pericytes—and combined them within a single platform. “This strategy allowed us to almost fully replicate the 3D cell structure found in the human body,” Modena says.Dec 6, 2021 · Abstract. The blood-brain barrier (BBB) is a semipermeable and extremely selective system in the central nervous system of most vertebrates, that separates blood from the brain's extracellular fluid. It plays a vital role in regulating the transport of necessary materials for brain function, furthermore, protecting it from foreign substances in ... Your blood-brain barrier (BBB) is a tightly locked layer of cells that defend your brain from harmful substances, germs and other things that could cause damage. It’s a key part of …The blood-brain barrier is a thick lining along the cerebral microvasculature that allows for the movement of certain ions, molecules, and cells to continue to move towards the brain. The thick lining of cells is wedged extremely close to each other, forming tight junctions. These tight junctions are what allow specific molecules to pass freely ...However, the mechanism of ZIKV crossing the physiological barrier to the central nervous systems (CNS) remains elusive. The placental barrier and the blood brain barrier (BBB) protect the fetus from pathogens and ensure healthy brain development during pregnancy. In this study, we used human placenta trophoblasts cells (JEG-3) and …What are the functions of the blood brain barrier? Protects the brain from "foreign substances" (xenobiotics) in the blood that may injure the brain. Protects the brain from hormones and neurotransmitters in the body. Maintains a constant environment for the brain. Not fully developed at birth.3) The blood-brain barrier is effective against the passage of: A) nutrients such as glucose B) metabolic waste such as urea C) water D) anesthetics E) alcohol B) metabolic waste such as urea See an expert-written answer!The blood–brain barrier (BBB) and the blood–cerebrospinal fluid barrier are the anatomic and physiologic structures that protect the sensitive central nervous system (CNS) homeostasis from exposure to molecules that are toxic or that would result in adverse neurologic effects. ... This has been shown to be an effective method to introduce ...The blood-brain barrier (BBB) is the specialized system of brain microvascular endothelial cells (BMVEC) that shields the brain from toxic substances in the blood, supplies brain tissues with nutrients, and filters harmful compounds from the brain back to the bloodstream. The close interaction between BMVEC and other components of the …

Flashcards Q-Chat Created by selina_do Terms in this set (35) The blood brain barrier is effective against the passage of.. metabolic waste such as urea Which of the following is a traumatic brain injury? The gray matter of the spinal cord.. Cell bodies of the sensory neurons of the spinal nerves are located in..

List and identify the major regions of the brain. Diencephalon; central core of forebrain: Thalamus; information relay station, Epithalamus; connect the limbic system to other parts of the brain. Hypothalamus; link the nervous system to the endocrine system via the pituitary gland. Brain Stem: Midbrain; involuntary movements, wakefulness ... Study with Quizlet and memorize flashcards containing terms like Which statement about HIV postexposure prophylaxis (PEP) for health-care workers is the most accurate? a. PEP should be started within hours of exposure. b. PEP should be started within 72 hours of exposure. c. Renal and hepatic function tests should be done 6 weeks after beginning …Study with Quizlet and memorize flashcards containing terms like Blood brain barrier, Structure of the blood brain barrier, Structure of the blood brain barrier 2 and more.The blood-brain barrier (BBB), a dynamic interface between blood and brain constituted mainly by endothelial cells of brain microvessels, robustly restricts the …Oct 21, 2023 · ANS: C Drugs cross the blood-brain barrier more readily in infants, making these patients more susceptible to central nervous system (CNS) side effects. Infants have a prolonged and irregular gastric emptying time and absorb drugs in the stomach more quickly. List and identify the major regions of the brain. Diencephalon; central core of forebrain: Thalamus; information relay station, Epithalamus; connect the limbic system to other parts of the brain. Hypothalamus; link the nervous system to the endocrine system via the pituitary gland. Brain Stem: Midbrain; involuntary movements, wakefulness ... 2. Methods: Search Strategy and Data Selection. Electronic databases, such as PubMed, Scopus, and ScienceDirect, were used for search by using “cannabinoids”, “cannabis“, “blood–brain barrier”, “brain delivery”, and “brain disposition” as the main keywords, starting from January 1971 to January 2020. In this review we ...

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"It will monitor if the medication already pass the blood brain barrier" A. "It will help determine if the medication dosage is still within the therapeutic level" Lithium levels determine whether an effective dose of lithium is being given to maintain a therapeutic level of the drug.Study with Quizlet and memorize flashcards containing terms like Which of the following statements concerning the blood-brain barrier is FALSE? a) Substances that are lipid-soluble can cross the blood-brain barrier readily. b) Penicillin is useless against infections of the brain because it is completely incapable of crossing the barrier. c) Most antibiotics cannot cross the blood-brain ... The blood-brain barrier protects the cerebrospinal fluid from contamination, and can be quite effective at excluding potential microbial pathogens. As a consequence of these defenses, there is no normal microbiota in the cerebrospinal fluid. The blood-brain barrier also inhibits the movement of many drugs into the brain, particularly compounds ...The physical barrier between blood and the CNS (the blood-brain barrier, the blood-spinal cord barrier and the blood-CSF barrier) protects the CNS from both toxic and pathogenic agents in the blood. It is now clear that disruption of the blood-CNS barrier plays a key role in a number of CNS disorders, particularly those associated with …it is a set of characteristics within the vessels and cells that prevent certain substances from entering the brain. These are the least permeable capillaries of the body. These excludes many potential harmful substances. They are useless against some substances. True or false. The BBB is a physical structure.Study with Quizlet and memorize flashcards containing terms like Antiepileptics include all of the following drugs, EXCEPT:, Before excretion, lithium is:, Comorbidity of bipolar disorder and substance abuse is associated with a greater risk of switching from a depressive episode to one of: and more.Blood-Brain Barrier (BBB) is a selectively permeable membrane regulates the passage of a multitude of large and small molecules into the microenvironment of the …The blood-brain barrier (BBB) is a complex and dynamic system that protects the brain from harmful substances and maintains its homeostasis. This article provides a comprehensive overview of the structure, function, impairment, and biomarkers of the BBB, as well as the current methods and challenges of studying it. It also reviews the latest advances and perspectives in BBB research, with a ...the blood-brain barrier is effective against. metabolic waste such as urea. A traumatic brain injury is. cerebral edema. the body is prepared for fight-or-flight by. the sympathetic nervous system. NOT a result of parasympathetic stimulation. dilation of the pupils. The blood-brain barrier (BBB) is a highly selective semipermeable border of endothelial cells that regulates the transfer of solutes and chemicals between the circulatory system and the central nervous system, thus protecting the brain from harmful or unwanted substances in the blood. The blood-brain barrier is formed by endothelial cells of the capillary wall, astrocyte end-feet ...Definition. Blood-Brain Barrier (BBB) is a selectively permeable membrane regulates the passage of a multitude of large and small molecules into the microenvironment of the neurons. It achieves this feat by with the aid of multiple cellular transport channels scattered along the membrane. These include: ….

A uniform ladder 5.0 m long rests against a frictionless, vertical wall with its lower end 3.0 m from the wall. The ladder weighs 160 N. The coefficient of static friction between the foot of the ladder and the ground is 0.40.Nov 15, 2020 · ABSTRACT. The blood-brain barrier (BBB), a dynamic interface between blood and brain constituted mainly by endothelial cells of brain microvessels, robustly restricts the entry of potentially harmful blood-sourced substances and cells into the brain, however, many therapeutically active agents concurrently cannot gain access into the brain at ... Blood Brain Barrier (BBB) Prevents circulating blood substances (bacteria and fungi) from reaching the CSF. Consists of: tight junctions between non-porous endothelial cells, basement membrane, astrocyte processes. Glucose and amino acids cross slowly by carrier mediated transport mechanism. Features of Brain Microvessels.T. True or False: Anticancer drugs do not cross the blood-placenta barrier. F. True or False: Ototoxicity can damage the eyes. F, it can cause damage to hearing and balance. True or False: Idiosyncratic means safe for children. F. True or False: The primary organ of metabolism is the kidneys. F It's the liver.Study with Quizlet and memorize flashcards containing terms like Voluntary muscle control is one of functions of the A) cerebellum. B) cerebrum. C) spinal cord. D) brain stem. E) meninges., Functions of the meninges include A) support for the brain and spinal cord. B) transmission of signals from the peripheral nervous system. C) protection from external shock. D) production of ...The blood–brain barrier is generally very effective at preventing unwanted substances from accessing the brain, which has a downside. The vast majority of potential drug treatments do not...A highly selective permeability barrier that separates the circulating blood from the brain extracellular fluid (BECF) in the CNS. It is formed by capillary endothelial cells, connected by tight junctions with an extremely high electrical resistivity of at least 0.1 Ω⋅m. The b.b.b. allows the passage of water, some gases, and lipid soluble ...Blood-Brain Barrier. Your blood-brain barrier (BBB) is a tightly locked layer of cells that defend your brain from harmful substances, germs and other things that could cause damage. It’s a key part of maintaining your brain health. It also holds good things inside your brain, maintaining the organ’s delicate chemical balance. blood brain barrier (functions) keeps blood cells, proteins, toxins, bacteria, etc. out of brain tissue ; preserves "optimal balance" of extracellular chemical composition within the brain. what gets through the BBB. anything small and lipid soluble ; for which specific transporters exist ; ex. oxygen, CO2, glucose, insulin, alcohol, drugs. The blood brain barrier is effective against quizlet, List and identify the major regions of the brain. Diencephalon; central core of forebrain: Thalamus; information relay station, Epithalamus; connect the limbic system to other parts of the brain. Hypothalamus; link the nervous system to the endocrine system via the pituitary gland. Brain Stem: Midbrain; involuntary movements, wakefulness ..., For example, Crizotinib, an oral selective small-molecular tyrosine kinase inhibitor, is an effective anti-cancer medicine but with poor activity against brain tumor metastases due to its low BBB ..., ABSTRACT. The blood-brain barrier (BBB), a dynamic interface between blood and brain constituted mainly by endothelial cells of brain microvessels, robustly restricts the entry of potentially harmful blood-sourced substances and cells into the brain, however, many therapeutically active agents concurrently cannot gain access into the brain at ..., Study with Quizlet and memorize flashcards containing terms like Voluntary muscle control is one of functions of the A) cerebellum. B) cerebrum. C) spinal cord. D) brain stem. E) meninges., Functions of the meninges include A) support for the brain and spinal cord. B) transmission of signals from the peripheral nervous system. C) protection from external shock. D) production of ..., What cells are important in composing the BBB? Endothelial cells, Astrocytes. Pericytes. How do endothelial cells differ in the BBB from the rest of circulation? -Lack fenestrations. -Have tight junctions. -lack pinocytotic vessels. -Lots of mitochondria for energy dependent transport proteins., MRI scans may be carried out for a variety of reasons, and will be accordingly targeted at specific zones of the body. Scans of the brain and spinal cord, for instance, not only look for brain and spinal cord injuries but also for signs of ..., Abstract. The blood-brain barrier (BBB) is a highly selective membrane barrier at the brain microvessel level that facilitates transport between the systemic circulation and the central nervous system. A growing body of evidence supports a major role for the BBB in the etiology and pathogenesis of multiple vascular and neurodegenerative disorders. , Blood-brain barrier useless against fats, respiratory gasses, and other fat-soluble substances (alcohol, nicotine, and anesthetics), that will diffuse easily into brain. Describe 3 different types of traumatic brain injuries., The blood brain barrier: delivery of opioids to the CNS. Analgesic efficacy of opioids depends on the relative ability to cross the BBB. Opioids currently in clinical use alleviate pain mostly by binding to MOR in the CNS; uptake into the brain, therefore, is critical for efficacy. ... Effective and responsible clinical use of opioids and their …, One possible way around the problem is to “trick” the blood–brain barrier into allowing passage of the drug. This is the so-called Trojan horse approach, in which the drug is fused to a ..., Abstract. The blood-brain barrier (BBB) provides significant protection against microbial invasion of the brain. However, the BBB is not impenetrable, and mechanisms by which viruses breach it are becoming clearer. In vivo and in vitro model systems are enabling identification of host and viral factors contributing to breakdown of the unique ..., The two major divisions of the nervous system are the. PNS and the CNS. All behavior is the product of. an organism's genetic endowment. an organism's experience. an organism's perception of the current situation. Proteins that bind to DNA and influence the rate at which particular structural genes will be expressed are called. , Study with Quizlet and memorize flashcards containing terms like All nucleated cells in a human body normally have: A. class I MHC molecules. B. class II MHC molecules. C. CD8 surface coreceptors. D. CD4 surface coreceptors., Why can it be more difficult to treat infections in the brain than in other locations? A. Neurotransmitters inhibit antibiotic activity. B. Antibiotics can be blocked by ..., One possible way around the problem is to “trick” the blood–brain barrier into allowing passage of the drug. This is the so-called Trojan horse approach, in which the drug is fused to a ..., Drug-protein binding plays a key role in determining the pharmacokinetics of a drug. The distribution and protein binding ability of a drug changes over a lifetime, and are important considerations during pregnancy and lactation. Although proteins are a significant fraction in plasma composition, they also exist beyond the bloodstream and …, The blood-brain barrier at the interface between the brain’s blood vessels and nerve cells acts as a vital gatekeeper to the brain, allowing essential nutrients and fluids to pass into the central nervous system and the web of our brain’s neurons while keeping out harmful toxins and bacterial infection. Yet this barrier is so effective that it can also …, The brain is well protected against microbial invasion by cellular barriers, such as the blood-brain barrier (BBB) and the blood-cerebrospinal fluid barrier (BCSFB). In addition, cells within the central nervous system (CNS) are capable of producing an immune response against invading pathogens. ... Harris et al. demonstrated that the …, Chapter 6. Barriers of the CNS. The first studies to demonstrate the existence of a selective barrier between the blood and the brain were done by Ehrlich in 1885 [ 173 ]. In a classic series of experiments, Ehrlich infused Evan’s blue dye intravenously into a rat and found that all organs in the body stained except for the brain., The blood-brain barrier is effective against the passage of: A) nutrients such as glucose B) metabolic waste such as urea C) water D) anesthetics E) alcohol A The sympathetic and parasympathetic nervous systems are subdivisions of the: A) autonomic nervous system B) voluntary nervous system C) somatic nervous system D) central nervous system E ..., The nanoparticles target a protein on tumor blood vessel cells called P-selectin. The nanoparticles improved the treatment in a model of aggressive pediatric brain cancer. Brain tumors are notoriously hard to treat. One reason is the challenge posed by the blood-brain barrier, a network of blood vessels and tissue with closely spaced cells., Other articles where placental barrier is discussed: drug: Reproductive system drugs: The so-called placental barrier and the blood-testis barrier impede certain chemicals, although both allow most fat-soluble chemicals to cross. Drugs that are more water-soluble and that possess higher molecular weights tend not to cross either the placental or the blood-testis barrier. In addition, if a drug ..., Find step-by-step Health solutions and your answer to the following textbook question: The blood-brain barrier is effective against which of the following? A. Nutrients such as glucose B. Anesthetics C. Alcohol D. Metabolic waste such as urea., Study with Quizlet and memorize flashcards containing terms like A) no medications exist for treatment of these infections. B) antibiotics damage nervous tissue. C) many antibiotics cannot penetrate the blood-brain barrier. D) the infections move along peripheral nerves. E) it is very difficult to determine the causative microbe., All of the following organisms cause meningitis EXCEPT A ... , Study with Quizlet and memorize flashcards containing terms like Which of the following would be an effective treatment for bacterial meningitis? cephalosporins MCV4 PCV Hib vaccine All of the above are correct., Which of the following statements concerning the blood-brain barrier is FALSE? Most antibiotics cannot cross the blood-brain barrier. Penicillin is useless against infections of the ..., a. Penicillin is useless against infections of the brain because it is completely incapable of crossing the barrier. b. Substances that are lipid-soluble can cross the blood-brain barrier readily. c. Most antibiotics cannot cross the blood-brain barrier. d. Inflammation can alter the blood-brain barrier, increasing the likelihood that a ... , Terms in this set (33) What is the function of the blood-brain barrier? Brain is sensitive to changes in ionic environment & vulnerable to toxins. -BBB provides physical, physiological & molecular barriers that provide a stable environment for neurons to fxn properly. -Need to be kept separate from systemic signaling., An NIH-supported study looked at treatment for ischemic stroke, which happens when one of our brain blood vessels is blocked. Trusted Health Information from the National Institutes of Health Some stroke patients may be able to receive effe..., The blood-brain barrier is usually effective at keeping foreign or toxic substances out of your central nervous system. Most of the time this is a good thing, but it can pose a problem when developing new drugs for the nervous system., Both cross the blood-brain barrier and S1, like gp120, is likely toxic to brain tissues. “It was like déjà vu,” said Banks, who has done extensive work on HIV-1, gp120, and the blood-brain barrier. The Banks’ lab studies the blood-brain barrier in Alzheimer’s, obesity, diabetes, and HIV. But they put their work on hold and all 15 people in the lab …, Biohazard. Hepatitis B _____ is administered by intramuscular injection in three doses. Vaccine. The most effective barrier against _____ is the unbroken skin. Infections. Proper hand washing depends on two factors: running water and: friction. Study with Quizlet and memorize flashcards containing terms like Any disease caused by the growth of ..., A) They can be purchased with a spermicide. B) They are reliable against pregnancy when used consistently. C) They can be used with baby oil and body lotions as lubricants. D) They help prevent the spread of some sexually transmitted infections., A primary advantage of the contraceptive sponge is that A) it does not use the spermicide …, The blood-brain barrier is formed by a tight junction between the endothelial cells, astrocytes, and the pericytes of the blood vessels. This makes the transport of substances from the blood to the brain very difficult and selective because the pore size is very small. , Study with Quizlet and memorize flashcards containing terms like Parasympathetic and sympathetic refer to the two branches of the, Neurotransmitter molecules are released into the small space between two neurons called the _____, Which of the following is the function of the blood-brain barrier created by glia in the brain? and more.