Pharm 7.1 Flashcards
Autonomic nervous systmem
activities are not under direct conscious control
Autonomic nervous systmem controls
primarily the visceral functions sucha s cardiac output, blood flow to various organs, heartrate, BP, digestion_necc for life
nervous system and endocrine system
many commonalities - high level of integration in the brain, extensive negative feedback, chemicals fro transmission of information
two types of fibers
pregangliionic (myleinated) and post gaglionci (non myelinated)
divided into
pANS and SANS
major neurotransmitters
Ach (PANS) and NE(SANS) _..but both ganglia use Ach
ORIGIN
Thoraco-lumbar
DISTRIB
Wide
GANGLIA
Away from organ
LENGTH OF FIBERS
Short preganglionic; Long postganglionic
NT
NE
FUNCTION
Stress
ORIGIN
Cranio-sacral
DISTRIB
Limited
GANGLIA
Close to organ
LENGTH OF FIBERS
Long preganglionic; Short postganglionic
NT
ACh
FUNCTION
Conserve energy
all preganglionci fibers and somatic (nonautonomic) motor fibers are
cholinergic
all postganglionic parasympathetic and a few sympathetic post ganglionic fibers are
cholinergic
enteric nervous system
a large and highly organized collection of neurons located in the walls of the gastrointestinal system functions independently of the CNS and controls the motility, exocrine and endocirne secretions, and cicrocirculation of GIT (sometimes considered a 3rd division of ANS)
ENS is a collections of
nerve fibers that innervate the GIT, pancreas, gall bladder and it constitues “brain of the gut”
ENS plexuses
myenteric plexus (the plexus of Aurbach) and the submucos plexus (the plexus of Meissner)
ENS is modulated by
SANS and PANS
Bear vs Couch
Sympathtic vs Parasympathetic
SANS responds to
stressful situations - fight or flight
Effects of stimulation of the sympathetic nervous system
increase BP and HR, mobilize energy stores of the body, increase blood flow to keletal muscles and the heart while diverting blood from the skin and internal organs, dialation of the pupils and bronchiles, affects GI motility and fn of bladder and sexual organs
SANS tens to fn as
a unit with diffuse distribution of post ganglionic fibers involved in a wide array of phsiological activities - complete system
PANS maintains
essential body functions (homeostasis) - rest and digest
PANS is not a
functional entity and never discharges as a complete system, but discrete PNS fibers are activated separately
Role of the CNS in autonomic control functions
ANS is a motor (efferent) system however requires sensory input from peripheral sturctures