Cardiovascular and endocrine responses to feeding in the young calf.

Abstract

SUMMARY1. A number of cardiovascular and endocrine responses which occur during and after feeding in the unweaned calf are described.2. There was a substantial increase in both heart rate and mean aortic blood pressure during feeding in these animals. This occurred within the first few seconds and persisted throughout the period of ingestion.3. The concentrations of glucose, insulin and gastrin in arterial plasma rose abruptly during, or immediately after, feeding and elevated values persisted for at least 2 hr. A transient increase in glucagon concentration was also observed. In contrast, feeding appeared to produce no immediate rise in enteroglucagon concentration.4. The adrenal output of glucocorticoids rose transiently in response to feeding but that of catecholamines was unaffected. 5. Cardiovascular responses to feeding were also examined in other species. In unweaned kids the changes were essentially similar to those observed in the calf but were less pronounced. In lambs a persistent hypertension occurred which was associated with a brief initial tachycardia. In adult dogs ingestion of solid food also caused tachycardia but although the aortic blood pressure rose for a short period at the beginning of feeding, hypotension developed thereafter.6. The possibility that both the cardiovascular and endocrine responses, which occur during or immediately after feeding, are mediated by the autonomic nervous system is discussed.

Cardiovascular responses to locomotor activity and feeding in unrestrained three-toed sloths, Bradypus variegatus

“…In the study of sheep cited above, BlairWest and Brook (18) not only observed increases in HR and BP similar to those seen in other species (1,4,5,15,17), but also noted the production of copious amounts of saliva. This resulted in a reduction in renal blood flow with the consequent retention of sodium and water, and a reduction in the circulatory volume with a rise in plasma renin concentrations (18).…”

“…These include alterations in blood pressure (BP), heart rate (HR), and blood flow to and from those tissues and organs that participate in neural and hormonal functions (1)(2)(3)(4)(5). Sleep, for example, is an activity accompanied by a fall in BP (6).…”

Effect of the interaction between food state and the action of estrogen on oxytocinergic system activity

“…The central administration of OT induces the expression of the FOS protein in regions involved in the control of food intake (Olson et al 1993). Plasma osmolality also increases in response to food intake and the ingestion of sodium (Bloom et al 1975, Houpt et al 1983, Burlet et al 1992; this increase involves both inhibitory and excitatory control mechanisms (Cunningham & Sawchenko 1991).…”

Absence d'effets d'un excès alimentaire en leucine sur les cinétiques postprandiales du glucagon et du cortisol plasmatiques chez l'agneau préruminant

“…1 ). Or, chez le veau préruminant un pic a été détecté au cours des 10 min qui suivent l'ingestion d'un repas témoin (Bloom et al, 1975). Aucune variation de la glucagonémie n'a été induite par l'excès alimentaire de leucine chez l'agneau préruminant ( fig.…”