Cystic Prostatic Hypertrophy in Two Inbred Lines of Syrian Hamsters 1

Abstract

Benign, spontaneous, prostatic hypertrophy is rare in laboratory rodents. In fact, the only reference in the literature relates to a proliferative hyperplasia of the prostate gland in female mastomys (1). Among experimental animals, only the age-dependent, cystic, spontaneous prostatic hypertrophy of the dog has been studied (2).

This report describes an age-dependent, cystic, spontaneous, prostatic hypertrophy of Syrian hamsters which appears to be genetically controlled, since it was found in only two of six inbred lines studied. 2

Materials and Methods. The animals studied were BIO® hamsters 3 (Mesocricetus auratus) of six pedigreed inbred lines developed at this Institute and characterized as follows:

Line 2.4—originated from London School of Hygiene, agouti color, inbred for 30 generations; longevity (expressed as the number of days during which half a population survives under standard conditions) is 532 days.

Line 87.20—originated from Ingham - Toolan-Gulf, rust color, inbred for 20 generations; longevity is 670 days.

Line 12.14—originated from Warren, cream color, inbred for 22 generations; longevity is 473 days. All males are affected by late-occurring, sex-linked, progressive hind-leg paralysis (3).

Line 40.54—originated from Schwentker-Toolan-LaCasse-Gulf, agouti and acromelanic white color, inbred for seven generations; longevity is unknown. All animals are affected by a hereditary (autosomal recessive) myopathy and cardiopathy.

Line 1.5—originated from the National Institutes of Health, acromelanic white color, inbred for 19 generations; longevity is 590 days; dental caries-susceptible (4).

Line 4.24—originated from Schwentker, agouti color, inbred for 36 generations; longevity is 589 days; obesity, high adrenal tumor incidence (5).

Male animals at about sexual maturity (60 days old) and males older than 150 days, were taken from a breeding colony which was maintained under standard conditions (temperature controlled at 65-72°F.; light exposure from 7:00 AM to 9:00 PM; Guilford breeder chow and Cambridge City water ad libitum with Ab-Sorb-Dri bedding). They were killed by intraperitoneal pentobarbital, pelvic organs were dissected, and the prostale was weighed, fixed in formaldehyde, and prepared for histological examinitation in hematoxylin-eosin-stained sections.)