Ganglia, Sympathetic Rats 42 rat 38 animal experiment 36 autonomic nervous system 36 endocrine system 36 Male 32 superior cervical ganglion 32 Animal 30 Rats, Inbred Strains 26 Norepinephrine 24 Pineal Gland 24 nonhuman 24 pineal body 24 noradrenalin 22 radioisotope 22 Female 20 Support, Non-U.S. Gov't 20 Animals 18 Thyroid Gland 16 propranolol 16 central nervous system 14 adrenergic system 12 Receptors, Adrenergic, alpha 10 Receptors, Adrenergic, beta 10 Superior cervical ganglion 10 Sympathectomy 10 drug efficacy 10 ganglionectomy 10 isoprenaline 10