peripheral nervous system Flashcards
PNS
somatic NS (voluntary)
and
Autonomic NS (involuntary)
*sympathetic. (SNS) and parasympathetic (PSNS)
Parasympathetic NS what it does to:
pupil
saliva prod
bronchi
heart
stomach, pancreas, and intestines
urination
erection
rest and digest:
*constricted pupil
*stimulates saliva production
*constricts bonchi
*slows heart
*stimulates stomach, pancreas and intestines
*stimulates urination
*does not promote erection
sympathetic NS what it does to:
pupil
saliva prod
bronchi
heart
epi and norepi
glucose
stomach, pancreas, and intestines
urination
erection
fight or flight:
*dilates pupil
*inhibits saliva production
*dilates bronchi
*accelerates heart
*stimulates epienephrine and norepinephrine release
*stimulates glucose release
*inhibits stomach, pancreas, and intestines
* inhibits urination
*promotes erection
SNS effects
↑ HR (+chronotropic)
↑ BP (vasoconstriction)
bronchial smooth muscle dilation
shunting of blood
mydriasis (pupil dilation) = ↑field of vision
mobilization of stored energy :
(↑glucose for brain and ↑ fatty acids for muscle activation)
PSNS
↓ HR (-chronotropic)
↑gastric secretion (motility)
↑bladder emptying
↑bowel emptying
miosis (pupil constriction - pupillary muscle contraction)
bronchial smooth muscle constriction
innervation control (PSNS)
most organs have dual innervation
*when one system is activated it will cause deactivation of the other or when one system is blocked it will cause the activation of the other
some organs have dual innervation that complement each other
ex: male reproduction: erection/ejaculation
a few have single innervation only
ex: sweat glans (SNS) or eye dilate or contrict
PNS neuotransmitters
4 total
Acetylcholine:
*the only transmitter for PSNS also the pre-ganglionic transmitter for the SNS
Epinephrine (adrenaline):
*maine transmitter for the adrenal medula (SNS)
Norepinephrine:
*the post-ganglionic transmitter for the SNS
Dopamine:
*precursor to norepinephrine (SNS)
