autonomic nervous system Flashcards
what does the autonomic nervous system control
involuntary functions - parasympathetic and sympathetic
what neurotransmitter do all preganglionic neurones use
they are all cholinergic and use Ach. release of Ach results in post ganglionic nicotinic receptors opening their channels
what are postganglionic neurotransmitters and receptors in the parasympathetic system
release ach and have muscarinic receptors
what are postganglionic neurotransmitters and receptors in the sympathetic system
release noradrenaline and are adrenoreceptors
name some other rarer types of neurotransmitter
ATP, NO, 5-hydroxytryptamine and neuropeptides
what is the 3rd domain of the autonomic nervous system ?
very complex and is called the enteric nervous system and is found in the GI tract
how is adrenaline released into the blood stream by the adrenal medulla
chromaffin cells act as postganglionic neurones and release adrenaline into the blood stream by exocytosis
what does parasympathetic release of Ach cause
bradycardia, bronchiole contraction, increase sweat/saliva, reduced cardiac conduction velocity
what does sympathetic release of noradrenaline cause
tachycardia, bronchiole dilation, increased glandular secretion
what do beat 1 adrenoreceptors cause
act by increasing the electrical conductivity and the force of the contraction of the heart
what do alpha 1 adrenoreceptors cause
vasoconstriction of most blood vessels
what do beta 2 adrenoreceptors cause
vasodilation of blood vessel in exercising muscles and airways
when do all B1, a1 and b2 receptors all become activated
when adrenaline/noradrenaline release is increased
