Disorder of salivary secretion in inbred polydipsic mouse.
To find mechanisms of an extreme polydipsia in an inbred strain of mice, STR/N, this study was undertaken using Institute of Cancer Research (ICR) mice as a control. During food deprivation, daily water intake of both strains decreased. The decrement in the STR/N mice was larger than that in the ICR mice. During dehydration, daily food intake of the STR/N mice was smaller than that of the ICR mice. These data indicate that prandial drinking was more severely affected for the STR/N mice. Under anesthesia, the stimulated salivary secretion by pilocarpine of the STR/N mice was significantly smaller than that of the ICR mice. The submandibular gland of the STR/N mice was lighter and harder than that of the ICR mice. After desalivation from the major three salivary glands, the ICR mice drank as much as the STR/N mice. Young STR/N mice with undeveloped polydipsia did not show different salivary secretion stimulated by pilocarpine from the young ICR mice. These findings indicate a dysfunction with age in the salivary glands of the STR/N mice, and they suggest that the decreased saliva induces thirst and triggers extraordinary drinking in the polydipsic mice.
Hamada
A
A
First Department of Operative Dentistry, Kyushu Dental College, Kokurakitaku, Kitakyushu 803-8580, Japan.
Inenaga
K
K
Nakamura
S
S
Terashita
M
M
Yamashita
H
H
D000367:Age Factors; D000818:Animals; D004326:Drinking / Q000502:physiology; D004327:Drinking Behavior / Q000502:physiology*; D004435:Eating / Q000502:physiology; D007274:Injections, Intraperitoneal; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D008817:Mice, Mutant Strains; D018721:Muscarinic Agonists / Q000494:pharmacology; D009929:Organ Size; D009994:Osmolar Concentration; D010862:Pilocarpine / Q000494:pharmacology; D012039:Regional Blood Flow / Q000187:drug effects; D012463:Saliva / Q000378:metabolism; D013361:Sublingual Gland / Q000098:blood supply / Q000187:drug effects / Q000378:metabolism*; D013363:Submandibular Gland / Q000098:blood supply / Q000187:drug effects / Q000378:metabolism*; D013894:Thirst / Q000502:physiology*
D018721:Muscarinic Agonists; D010862:Pilocarpine