[Opposite modulating effects of the hypothalamic region on cardiac reflexes of Gadus morhua cod and Rana temporaria frogs].
The effects of hypothalamic stimulation on cardiac reflexes have been investigated in the cod Gadus morhua and frog Rana temporaria. Cardiac reflexes were elicited by electrical stimulation of the medullar vagal lobes in fishes and central end of cardiac vagal branch in frogs. During simultaneous or successive stimulation of the hypothalamic region and vagal structures, modulation of the reflexes was observed. Reflex bradycardia was either augmented or inhibited, indicating the corresponding pattern of hypothalamic influences. No correlation was found between the parameters of stimulation, reflex intensity, hypothalamic region and the pattern of modulating influences. The data obtained suggest the existence of opposite modulating influences of the hypotalamic region upon parasympathetic reflexes in the heart of fishes and frogs.
D000818:Animals; D001001:Anura; D001931:Brain Mapping; D004027:Diencephalon / Q000502:physiology; D004558:Electric Stimulation; D005399:Fishes / Q000502:physiology; D006321:Heart / Q000294:innervation*; D007031:Hypothalamus / Q000502:physiology*; D008526:Medulla Oblongata / Q000502:physiology; D011896:Rana temporaria / Q000502:physiology; D012018:Reflex / Q000502:physiology*; D014630:Vagus Nerve / Q000502:physiology*
Raznonapravlennye moduliruiushchie vliianiia gipotalamicheskoĭ oblasti na serdechnye refleksy u treski Gadus morhua i liagushki Rana temporaria.