The Effect of Octreotide on Kainate-Induced Wet Dog Shakes and Seizure Activity in Male and Female Rats

Abstract

Systemic kainic acid (KA) administration to rats triggers wet dog shakes (WDS) followed by epileptic seizures. Although WDS are often associated with the occurrence of seizures, we have recently shown that following nitric oxide (NO) synthesis inhibition, the number of WDS decreased; subsequently the onset of seizure activity was shortened, and the number of convulsions was increased. Somatostatin (SS), whose release appears to be controlled by NO, inhibits seizure activity. There are sex differences in seizure susceptibility as well as in SS and NO activities in brain. The present study was undertaken to assess the effect of octreotide (OC), a stable SS analogue, on KA-induced WDS and seizures in rats, with emphasis on possible sex differences. WDS and seizures were induced by KA in male and female (proestrus) Sprague Dawley rats; OC or saline was injected 30 min before KA and the behavior was monitored for 120 min after KA. Octreotide increased the number of WDS and decreased the number of convulsions; this effect was more pronounced in males. Onset of KA-induced seizure activity was earlier in females than males; however, there was no effect of OC on seizure latency. Seizure activity started after the termination of WDS. These results show OC has opposite effects on WDS and convulsions, in that it stimulates the former and inhibits the latter. These results support our previous findings that WDS and seizure activity involve separate mechanisms and suggest that WDS may have an inhibitory effect on limbic seizures.

Differential GABAA Subunit Expression Following Status Epilepticus in Seizure‐prone and Seizure‐resistant Rats: A Putative Mechanism for Refractory Drug Response

“…WDS are defined as intermittent paroxysmal shaking of the head, neck, and trunk and can occur in response to chemical or electrical stimulation of limbic structures (19). It is interesting to note that WDS are often associated with a delayed progression to convulsive seizures (20, 21). Consistent with this observation, and in contrast to the Fast rats, Slow rats spent prolonged periods exhibiting WDS without the manifestation of any convulsive behavior.…”

The Effect of Progesterone on Total Brain Tissue Sialic Acid Levels in Experimental Epilepsy

“…It is frequently reported that epilepsy may be affected by reproductive hormones, complicating the reproductive health in men and women, who experience changes in seizure frequency and severity with changes in reproductive cycles, at puberty, menstrual cycle, pregnancy, and even at menopause (see Beyenburg et al, 2001;Dagci et al, 2002;Tan & Tan, 2001;Tan et al, 2002). Ovarian steroids alter neuronal excitability at the membrane and in the genome.…”

Effects of Progesterone on Total Brain Tissue Adenosine Deaminase Activity in Experimental Epilepsy

“…Epilepsy may be affected by sex hormones, complicating the reproductive state in men and women, exhibiting changes in seizure frequency, and severity following many hormonal cycles (Beyenburg et al, 2001;Dagci, Koylu, Tan, Yan, & Pogun, 2002;Tan & Tan, 2001;Tan, Kalyoncu, & Tan, 2002). Animal models have been used to understand the interrelation between hormones and epilepsy in humans.…”