کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2843376 1166090 2012 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Autonomic control of heart rate is virtually independent of temperature but seems related to the neuroanatomy of the efferent vagal supply to the heart in the bullfrog, Lithobathes catesbeianus
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم کشاورزی و بیولوژیک (عمومی)
پیش نمایش صفحه اول مقاله
Autonomic control of heart rate is virtually independent of temperature but seems related to the neuroanatomy of the efferent vagal supply to the heart in the bullfrog, Lithobathes catesbeianus
چکیده انگلیسی

Bullfrogs, Lithobathes catesbeianus, bearing a femoral artery cannula were held at 3 temperatures (10, 20 and 30 °C) for 24 h. Changes in heart rate were recorded before and after injection of cholinergic and adrenergic antagonists. Normal heart rate doubled for each temperature increment. Adrenergic tone on the heart varied around 20% at all 3 temperatures but cholinergic tone increased from −5% to 10% between 10 and 30 °C. In contrast, cholinergic tone increased from 75% at 5 °C to 329% at 25 °C in Xenopus laevis. Injection of the neural tracer True Blue into the cervical vagus of the bullfrog revealed a single location for vagal preganglionic neurons (VPN) in the dorsal vagal motor nucleus (DVN), while Xenopus had 30% of its VPN in a ventro-lateral group outside the DVN. Broader comparative studies have suggested that differences in the extent of vagal tone may relate to the location of VPN in the brainstem and this may be the case in these amphibians.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Thermal Biology - Volume 37, Issue 3, April 2012, Pages 243–247
نویسندگان
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