Ultrastructural changes in the rat carotid body in severe haemorrhagia.
Rat carotid bodies were studied electron microscopically after short-term severe hypovolaemia, which is known to induce a marked chemoreceptor activation in the carotid body.  Altogether 84 nerve-endings in the hypovolaemic rats' carotid bodies and 91 nerve-endings in the control carotid bodies were investigated.  An increased accumulation of the glomus cell granular vesicles near the synaptic specializations of the nerve-endings was observed after hypovolaemia.  Moreover, a statistically significant increase in the contacts between the nerve-ending synaptic specializations and the glomus cell granular vesicles was observed after hypovolaemia.  A suggestion was made that the glomus cells might act as modulating, probably inhibitory, interneurones, whose catecholamines are responsible for the inhibition.
D000818:Animals; D002344:Carotid Body / Q000473:pathology*; D005260:Female; D006470:Hemorrhage / Q000473:pathology*; D007395:Interneurons; D008297:Male; D008854:Microscopy, Electron; D009411:Nerve Endings; D051381:Rats; D013569:Synapses; D013997:Time Factors