Nitric oxide-dependent mitotic activity in salivary glands of the rat upon sympathetic stimulation

• Incorporation of [3H]thymidine into trichloroacetic acid (TCA)-insoluble material of the parotid and submandibular glands was used as an index of mitotic activity following unilateral electrical stimulation of the sympathetic innervation (20 Hz, 4 min every fifth minute over 34 min). Stimulation under β-adrenoceptor blockade (propranolol 2 mg/kg, intravenous) alone or combined with α-adrenoceptor blockade (phentolamine 2 mg/kg, intravenous) did not increase the rate of [3H]thymidine incorporation into the two types of glands. However, under α-adrenoceptor blockade the [3H]thymidine incorporation increased into the parotid glands, by 122% (compared to the glands on the contralateral side), but not into the submandibular glands. In the presence of the neuronal type NO-synthase (nNOS) blocker N-PLA (30 mg/kg, intravenous) or the unselective NO-synthase blocker L-NAME (30 mg/kg, intravenous), this increase was reduced to 49 and 47%, respectively. Thus, the major part of the sympathetically nerve-evoked β-adrenoceptor-mediated mitotic response was found to depend on the activity of neuronal type NO-synthase to generate NO. Since the sympathetic nerve fibres of the parotid gland lack NO-synthase, the neuronal type NO-synthase subjected to the inhibitors is likely to be of parenchymal origin. © 2004 Elsevier Ltd. All rights reserved.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Odontologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Dentistry (hsv//eng)

Nyckelord

β-Adrenoceptors

Mitosis

Nitric oxide synthase

Salivary glands

Sympathetic nerve stimulation

alpha adrenergic receptor blocking agent

beta adrenergic receptor blocking agent

nitric oxide

phentolamine

propranolol

adrenergic system

animal

article

cytology

drug effect

electrostimulation

female

innervation

parotid gland

physiology

rat

salivary gland

Sprague Dawley rat

submandibular gland

Adrenergic alpha-Antagonists

Adrenergic beta-Antagonists

Animals

Electric Stimulation

Rats

Rats

Sprague-Dawley

Sympathetic Nervous System

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)