Lasting consistency of cold adaptability in rats reared in cold for many generations.
نویسندگان
چکیده
Wistar rats were successively reared in cold at 5 degrees C from 1969 to 1984. The historical changes observed in these rats were reported. The cold-adapted rats reared in cold for 8 to 11 successive generations (C8-11G) were examined on their cold tolerance and non-shivering thermogenesis. C8-11G rats showed greater nonshivering thermogenesis than that of the warm-adapted control group (W), and rats exposed to cold for periods of 2 to 8 weeks (C). The nonshivering thermogenesis of C8-11G rats was diminished to a similar level to that of W and C rats by administration of a ganglion blocker, of reserpine, or of beta-adrenoceptor blocker. The de-adapted rats reared in warm at 25 degrees C for 3 generations after being reared for many generations in cold (DA-3G) showed much more nonshivering thermogenesis as compared to W rats. Cold tolerance of DA-3G rats was at a level of intermediate between that of W and C rats. Brown adipose tissue (BAT) weight of DA-3G rats was similar to that of C rats, while chemical composition of BAT in DA-3G rats differed from that of C and W rats.
منابع مشابه
Muscle and brown adipose tissue fatty acid profiles in cold-exposed rats.
Effects of cold acclimation and cold exposure for 25 generations on triglyceride (TG)-, total phospholipid (PL)-, and cardiolipin (CL)-fatty acid (FA) compositions were studied in the different types of skeletal muscles (red and white muscles from quadriceps, and soleus) as well as brown adipose tissue (BAT) in rats. TG: in cold-acclimated rats (CA) and rats reared in cold for 25 generations (2...
متن کاملEffect of early cold exposure on the endocrine responses of broiler chickens and the incidence of ascites syndrome.
Two hundred and fifty day-old broiler chickens were housed in a high altitude farm and divided in two experimental groups (cold-exposed and control). At the age of 3 and 4 d, the cold-exposed chickens were exposed to 15?C for 3 h, while the control birds were reared under normal condition. During the period between 14 and 28 days, both groups of chickens were exposed to a low environmental temp...
متن کاملEvaluation of Laying Performance and Egg Qualitative Characteristics of Indigenous Hens Reared in Rural Areas of Isfahan Province
This study was carried out to investigate the egg production performance and egg quality characteristics of the indigenous chickens reared in rural areas of two different climates of Isfahan province. Totally, 2160 indigenous chickens were studied in this research. Two dominant climatic regions (cold and hot) were determined for Isfahan province. In each climate, two towns and three villages...
متن کاملEvaluation of Thyroid Hormones, Blood Gases, Body Antioxidant Status, the Activity of Blood Enzymes and Bone Characteristics in Broiler Chickens with Cold Induced Ascites
A total of 150 day old female chickens (Ross 308) were randomly allocated to 2 groups with 5 replicate and 15 chicks in each replicate to determine the effects of cold induced ascites on performance, antioxidant status, blood enzyme activities and bone metabolism. The two experimental treatments were: 1) chicks that reared under normal temperature (NT) and 2) chicks that reared under cold tempe...
متن کاملReduced rearing temperature augments responses in sympathetic outflow to brown adipose tissue.
Sympathetic outflow to brown adipose tissue (BAT) contributes to both thermoregulation and energy expenditure in rats through regulation of BAT thermogenesis. Acute cold exposure in mature animals augments BAT thermogenesis; however, the enhanced BAT thermogenic response returns to normal shortly after cessation of the cold exposure. In this study, we sought to determine whether cold exposure i...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- The Japanese journal of physiology
دوره 35 3 شماره
صفحات -
تاریخ انتشار 1985