Behavioural, histological and cytokine responses during hyperalgesia induced by carrageenan injection in the rat tail.

We produced experimental inflammatory hyperalgesia by injecting carrageenan into the tail of Sprague-Dawley rats. We compared the rats' voluntary running wheel activity following carrageenan injection into the tail to that after carrageenan injection into the hind paw, the conventional site of inflammation, to identify whether the site of inflammatory-induced hyperalgesia altered voluntary activity. We also measured voluntary running before and after injection of carrageenan or saline into the tail or hind paw, and in separate groups of rats we measured the nociceptive response and the associated pro-inflammatory cytokine profiles following a carrageenan injection into the tail.

Cytokine profiles during carrageenan-induced inflammatory hyperalgesia in rat muscle and hind paw.

Unlabelled: It is not known if a cytokine cascade develops during muscle inflammation and whether cytokines contribute to muscle inflammatory pain. We measured plasma and tissue cytokine concentrations, and behavioral responses to noxious mechanical stimuli, after inducing inflammation in the gastrocnemius muscle and the hind paw of rats. Tissue and plasma samples were taken 3, 6, or 24 h after carrageenan or saline injection into one of the 2 sites.

Endotoxin preconditioning protects neurones from in vitro ischemia: role of endogenous IL-1beta and TNF-alpha.

We have examined whether changes in the expression of several inflammatory factors mediate the neuroprotective action of LPS preconditioning on cerebellar granule neurones (CGN) exposed to the mitochondrial toxin 3-nitropropionic acid (3-NP), chosen as an in vitro ischemic model. CGN were either directly pre-treated with LPS or indirectly by exposure to conditioned medium (CM) from LPS-treated mixed glial cultures obtained from wild type or IL-1beta-knock out mice. Following this pre-treatment CGN were incubated with 3-NP and cell viability assessed.

Fever and lethargy induced by subcutaneous pyrogen infusion in unrestrained rats.

We have investigated the effects of continuous subcutaneous infusion of lipopolysaccharide (LPS), muramyldipeptide (MDP), or saline on abdominal temperature and voluntary activity in unrestrained rats. Both pyrogens were infused via osmotic pumps at a rate of approximately 2 microg.kg-1.

Alteration in diel activity patterns as a thermoregulatory strategy in black wildebeest (Connochaetes gnou).

The nychthemeral activity patterns of a population of female black wildebeest inhabiting a shadeless environment were surveyed periodically over 1 year. The wildebeest fed mostly at night, with the proportion of feeding at night increasing when ambient conditions were hotter. Inactive periods were spent mostly lying during cooler weather but standing as days became hotter.