PHA 4107 Lecture Notes - Lecture 7: Detrusor Urinae Muscle, Adrenergic Receptor, Adrenergic
12 Jul 2018
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Document Summary
How does the activation of sympathetic system relax the bladder while tightening the urinary sphincter (both are smooth muscles): due to the expression of different adrenergic receptor subtypes i each muscle. Some generalizations: activation of (cid:573)1 and (cid:574)1 receptors tend to cause stimulatory responses, activation of (cid:573)2 and (cid:574)2 receptors tend to cause inhibitory responses, e causes a significantly greater response than ne when activating (cid:574)2. How can the activation of the sympathetic system case the vasodilation of some blood vessels and the vasoconstriction of other blood vessels? receptors: depends on the neurotransmitter and the receptor type. Noncatecholamines: although structurally similar to catecholamines, noncatecholamines differ from catecholamines in three important ways, are useable orally, can cross the blood-brain barrier, not rapidly metabolized by mao or comt, they have much longer half-lives than the catecholamines. Note: although these substances are often defined as specific for one subtype of receptors, this effect is always relative; specificity can be lost at higher doses.
