[Influence of stimulation of the central gray matter on low- and high-threshold startle reflexes].
Influences of the periaqueductal gray matter (PAG) stimulation on high-threshold jaw opening reflex (JOR) evoked by tooth pulp stimulation and on two functional types of startle reflexes were studied in chloralose anesthetized cats; the startle reflexes were high-threshold ones evoked by intense peripheral nerve stimulation (spino-bulbo-spinal, SBS, reflex) and low-threshold ones evoked by tactile stimuli (tactile spino-reticulo-spinal, TSRS, reflex). Stimulation of the majority of PAG sites induced considerable inhibition of JOR as well as profound depression of SBS-reflexes and moderate depression of TSRS-reflexes. Some PAG sites were found to exert a facilitatory action on the latter reflex. Effects of PAG stimulation were short-term (hundred ms) and/or long-lasting (minutes). Possible mechanisms of these effects are discussed.
Gokin
A P
AP
Karpukhina
M V
MV
Limanskiĭ
Iu P
IuP
D000818:Animals; D002415:Cats; D010487:Periaqueductal Gray / Q000502:physiology*; D010812:Physical Stimulation; D013216:Reflex, Startle / Q000502:physiology*
Vliianie stimuliatsii tsentral'nogo serogo veshchestva na nizko- i vyusokoporogovye refleksy vzdragivaniia.