Читать книгу Manual of Equine Anesthesia and Analgesia - Группа авторов - Страница 363

 Acetylcholine (ACh) and norepinephrine (NE) are the main neurotransmitters.

 All preganglionic neurons are cholinergic in both the SNS and PNS nervous systems and secrete ACh.

 Postganglionic neurons of the PNS are cholinergic, while most postganglionic SNS neurons are adrenergic and secrete NE.The adrenal gland functions like a modified sympathetic ganglion and when stimulated by presynaptic SNS fibers, releases NE and epinephrine (EPI) into the circulation to act on sites distant from the gland; therefore, there is no postganglionic neuron.Sweat glands in horses are mostly apocrine and open into hair follicles. These glands and the piloerector muscles are stimulated by circulating EPI that acts on adrenergic (β2) receptors.Eccrine sweat glands are common in humans, but are less common in horses. In humans, they constitute 90% of sweat glands and they are stimulated by a postganglionic SNS neuron that secretes ACh.