[Central neuronal pathways in the Bezold-Jarisch reflex in rats].
The distribution of the Fos-immunoreactive (Fos-ir) and NADPH-diaphorase-positive/NOS-containing neurons in the medulla and thoracic spinal cord in rats was studied after the veratrine injection into v. jugularis ext. followed by reproduction of the Bezold-Jarisch reflex. Fos-ir neurons were found in the nucleus tractus solitarius (Sol), coudoventrolateral (CVL) and rostroventrolateral (RVL) areas, intermediate reticular nucleus (IRt), and lateral paragiganrocellular nucleus (LPGi) of the medulla. The intensity of c-fos expression was as follows: Sol > CVL > RVL > LPGi. The intensity of NADPH-diaphorase reactivity was manifested in the following sequence: Sol > IRt > LPGi > RVL. In comparison to sham-operated animals, application of veratrine is associated with a statistically significant increase (P < 0.01) of the mean number of Fos-ir neurons in the Sol and CVL, but not in the RVL. Double-labelling (Fos + NA DPH) was found in a small number (about 2%) of neurones in the Sol, IRt and LPGi. In the thoracic spinal cord Fos-ir neurons were predominantly detected in the superficial layers of the dorsal horn, area around the central canal and the intermediate lateral or medial nuclei (IMl and IMM), where NOS-containing neurons in the thoracic spinal cord were accumulated. Received data show that signals arising from the veratrine-activated cardiopulmonary afferents activate neurons of the Sol and CVL that together with the RVL are incorporated into neuronal circuits for generation of the Bezold-Jarisch reflex. In the medulla NOS-containing neurons activated by input from cardiopulmonary receptors can contribute to the enhancement of cardioprotective depressor reflexes in the rats.
Maĭs'kyĭ
V O
VO
O. O. Bogomoletz Institute of Physiology, National Academy of Science of Ukraine, Kyiv.
Piliavs'kyĭ
O I
OI
Maznychenko
A V
AV
Datsenko
V V
VV
Pavliuchenko
V B
VB
Kostiukov
O I
OI
Moĭbenko
O O
OO
D000344:Afferent Pathways / Q000187:drug effects / Q000502:physiology; D000818:Animals; D017704:Baroreflex / Q000187:drug effects / Q000502:physiology*; D002628:Chemoreceptor Cells / Q000502:physiology; D015870:Gene Expression / Q000187:drug effects / Q000502:physiology; D007150:Immunohistochemistry; D008297:Male; D008526:Medulla Oblongata / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D009252:NADPH Dehydrogenase / Q000378:metabolism; D009475:Neurons, Afferent / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism / Q000502:physiology*; D016760:Proto-Oncogene Proteins c-fos / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D012021:Reflex, Abnormal / Q000187:drug effects / Q000502:physiology*; D013116:Spinal Cord / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D014630:Vagus Nerve / Q000502:physiology; D014702:Veratrine / Q000494:pharmacology
D016760:Proto-Oncogene Proteins c-fos; D009252:NADPH Dehydrogenase; D014702:Veratrine