Influence of glucagon and neurohypophysial hormones on plasma free fatty acid levels in the pigeon

Flight Effects on Plasma Levels of Neurohypophysial Hormones in Homing Pigeons

“…That AVT has indeed an adipokinetic action has been demonstrated in pigeon in vivo and also in in vitro experi ments [56] using pigeon adipose tissue slices [57], an action that may be mediated by cAMP [58], In this context, it may be men tioned that the release of AVT from the poste rior lobe in migratory birds prior to migration has been considered as an important event in the initiation of Spring migratory activity [59]. It should, however, be conceded that in birds, AVT is not to be regarded as a principal adipokinetic hormone like glucagon but could be more effective by its synergistic action with glucagon [51 ].…”

“…It is now well established that during sus tained muscular activity, birds metabolize fat as the chief fuel [49][50][51][52][53], Marked increases in postflight plasma levels of triglycerides, free fatty acids (FFA), glucagon and growth hor mone (GH) have been reported in homing pigeons [23,54], Increases in plasma levels of FFA and GH have also been shown in pigeons subjected to heat stress and dehydration [55], The observation that plasma levels of AVT are increased in heat-stressed domestic fowl [ 14] suggests that AVT may have a lipolytic action besides its well-known role as an anti diuretic hormone. That AVT has indeed an adipokinetic action has been demonstrated in pigeon in vivo and also in in vitro experi ments [56] using pigeon adipose tissue slices [57], an action that may be mediated by cAMP [58], In this context, it may be men tioned that the release of AVT from the poste rior lobe in migratory birds prior to migration has been considered as an important event in the initiation of Spring migratory activity [59].…”

Flight Effects on Plasma Levels of Neurohypophysial Hormones in Homing Pigeons

“…That AVT has indeed an adipokinetic action has been demonstrated in pigeon in vivo and also in in vitro experi ments [56] using pigeon adipose tissue slices [57], an action that may be mediated by cAMP [58], In this context, it may be men tioned that the release of AVT from the poste rior lobe in migratory birds prior to migration has been considered as an important event in the initiation of Spring migratory activity [59]. It should, however, be conceded that in birds, AVT is not to be regarded as a principal adipokinetic hormone like glucagon but could be more effective by its synergistic action with glucagon [51 ].…”

“…It is now well established that during sus tained muscular activity, birds metabolize fat as the chief fuel [49][50][51][52][53], Marked increases in postflight plasma levels of triglycerides, free fatty acids (FFA), glucagon and growth hor mone (GH) have been reported in homing pigeons [23,54], Increases in plasma levels of FFA and GH have also been shown in pigeons subjected to heat stress and dehydration [55], The observation that plasma levels of AVT are increased in heat-stressed domestic fowl [ 14] suggests that AVT may have a lipolytic action besides its well-known role as an anti diuretic hormone. That AVT has indeed an adipokinetic action has been demonstrated in pigeon in vivo and also in in vitro experi ments [56] using pigeon adipose tissue slices [57], an action that may be mediated by cAMP [58], In this context, it may be men tioned that the release of AVT from the poste rior lobe in migratory birds prior to migration has been considered as an important event in the initiation of Spring migratory activity [59].…”

Flight Effects on Plasma Levels of Neurohypophysial Hormones in Homing Pigeons

“…That AVT has indeed an adipokinetic action has been demonstrated in pigeon in vivo and also in in vitro experi ments [56] using pigeon adipose tissue slices [57], an action that may be mediated by cAMP [58], In this context, it may be men tioned that the release of AVT from the poste rior lobe in migratory birds prior to migration has been considered as an important event in the initiation of Spring migratory activity [59]. It should, however, be conceded that in birds, AVT is not to be regarded as a principal adipokinetic hormone like glucagon but could be more effective by its synergistic action with glucagon [51 ].…”

“…It is now well established that during sus tained muscular activity, birds metabolize fat as the chief fuel [49][50][51][52][53], Marked increases in postflight plasma levels of triglycerides, free fatty acids (FFA), glucagon and growth hor mone (GH) have been reported in homing pigeons [23,54], Increases in plasma levels of FFA and GH have also been shown in pigeons subjected to heat stress and dehydration [55], The observation that plasma levels of AVT are increased in heat-stressed domestic fowl [ 14] suggests that AVT may have a lipolytic action besides its well-known role as an anti diuretic hormone. That AVT has indeed an adipokinetic action has been demonstrated in pigeon in vivo and also in in vitro experi ments [56] using pigeon adipose tissue slices [57], an action that may be mediated by cAMP [58], In this context, it may be men tioned that the release of AVT from the poste rior lobe in migratory birds prior to migration has been considered as an important event in the initiation of Spring migratory activity [59].…”

Flight Effects on Plasma Levels of Neurohypophysial Hormones in Homing Pigeons

“…That AVT has indeed an adipokinetic action has been demonstrated in pigeon in vivo and also in in vitro experi ments [56] using pigeon adipose tissue slices [57], an action that may be mediated by cAMP [58], In this context, it may be men tioned that the release of AVT from the poste rior lobe in migratory birds prior to migration has been considered as an important event in the initiation of Spring migratory activity [59]. It should, however, be conceded that in birds, AVT is not to be regarded as a principal adipokinetic hormone like glucagon but could be more effective by its synergistic action with glucagon [51 ].…”

“…It is now well established that during sus tained muscular activity, birds metabolize fat as the chief fuel [49][50][51][52][53], Marked increases in postflight plasma levels of triglycerides, free fatty acids (FFA), glucagon and growth hor mone (GH) have been reported in homing pigeons [23,54], Increases in plasma levels of FFA and GH have also been shown in pigeons subjected to heat stress and dehydration [55], The observation that plasma levels of AVT are increased in heat-stressed domestic fowl [ 14] suggests that AVT may have a lipolytic action besides its well-known role as an anti diuretic hormone. That AVT has indeed an adipokinetic action has been demonstrated in pigeon in vivo and also in in vitro experi ments [56] using pigeon adipose tissue slices [57], an action that may be mediated by cAMP [58], In this context, it may be men tioned that the release of AVT from the poste rior lobe in migratory birds prior to migration has been considered as an important event in the initiation of Spring migratory activity [59].…”