๐”– Bobbio Scriptorium
โœฆ   LIBER   โœฆ

The pineal complex and melatonin affect the expression of the daily rhythm of behavioral thermoregulation in the green iguana

โœ Scribed by G. Tosini; M. Menaker

Publisher
Springer
Year
1996
Tongue
English
Weight
839 KB
Volume
179
Category
Article
ISSN
0340-7594

No coin nor oath required. For personal study only.

โœฆ Synopsis

Daily variation in the body temperature of the green iguana (Iguana iguana) was studied by telemetry in laboratory photo-thermal enclosures under a 12Light:12Dark (L:D) photoperiod. The lizards showed robust daily rhythms of thermoregulation maintaining their body temperatures (Tb) at higher levels during the day than during the night. Some animals maintained rhythmicity when kept in constant darkness. On light:dark cycles parietalectomy produced only a transient increase of median Tb in the first or second night following the operation. Pinealectomized lizards on the other hand maintained their body temperatures at significantly lower levels during the day and at significantly higher levels during the night than did sham-operated or intact lizards. This effect was apparently permanent, since one month after pinealectomy lizards still displayed the altered pattern. Plasma melatonin levels in intact animals were high during the night and low during the day and were unaffected by parietalectomy. Pinealectomized lizards showed low levels of plasma melatonin during both the day and the night. A daily intraperitoneal injection of melatonin in pinealectomized animals given a few minutes after the light to dark transition decreased the body temperatures selected by the lizards during the night and increased the body temperatures selected during the following day. Control injections of saline solution had no effect. The significance of these results is discussed in relation to the role of the pineal complex and melatonin in the mediation of thermoregulatory behavior.

๐Ÿ“œ SIMILAR VOLUMES

Circadian locomotor rhythms in the deser
Circadian locomotor rhythms in the desert iguana I. The role of the eyes and the pineal
โœ Daniel S. Janik; Michael Menaker ๐Ÿ“‚ Article ๐Ÿ“… 1990 ๐Ÿ› Springer ๐ŸŒ English โš– 863 KB

The pineal and the eyes are known to be important components in the circadian system of some species of lizards; their effects may be mediated by the hormone melatonin. We examined the role played by these structures in the desert iguana (Dipsosaurus dorsalis). Surgical removal of the pineal had no

Pineal involvement in the control of beh
Pineal involvement in the control of behavioral thermoregulation of the white sucker,Catostomus commersoni
โœ Kavaliers, Martin ;Ralph, Charles L. ๐Ÿ“‚ Article ๐Ÿ“… 1980 ๐Ÿ› John Wiley and Sons ๐ŸŒ English โš– 200 KB

## Abstract White suckers select a higher body temperature at night and a lower temperature during daytime. Removal of the pineal organ eliminated their diel rhythm of behavioral thermoregulation. After pinealectomy fish failed to select a lower daytime temperature. These results suggest that the p

Pineal and retinal melatonin is involved
Pineal and retinal melatonin is involved in the control of circadian locomotor activity and body temperature rhythms in the pigeon
โœ Itsuki Oshima; Hideki Yamada; Maki Goto; Koji Sato; Shizufumi Ebihara ๐Ÿ“‚ Article ๐Ÿ“… 1989 ๐Ÿ› Springer ๐ŸŒ English โš– 957 KB

Although pinealectomy or blinding resulted in loss of the clarity of the free-running rhythm of locomotor activity and body temperature and reduced the peak level of circulating melatonin rhythms to approximately a half in intact pigeons, neither pinealectomy nor blinding abolished any of these rhyt

Expression of tranferrin receptors in th
Expression of tranferrin receptors in the pineal gland of postnatal and adult rats and its alteration in hypoxia and melatonin treatment
โœ C. Kaur; V. Sivakumar; E. A. Ling ๐Ÿ“‚ Article ๐Ÿ“… 2006 ๐Ÿ› John Wiley and Sons ๐ŸŒ English โš– 897 KB

## Abstract Transferrin receptors (Tfrc) are membrane bound glycoproteins which function to mediate cellular uptake of iron from transferrin. We examined expression of Tfrc in the pineal gland of rats of different ages from 1 day to 12 weeks. The __mRNA__ and protein expression of Tfrc increased up