Lethargic mouse

Burgess DL, Biddlecome GH, McDonough SI, Diaz ME, Zilinski CA, Bean BP, Campbell KP, Noebels JL (1999) beta subunit reshuffling modifies N- and P/Q-type Ca2+ channel subunit compositions in lethargic mouse brain. Mol Cell Neurosci 13 293-311. 

A deletion in the mouse (34 gene (Cchb4) has been associated with the lethargic (Ih) phenotype (Burgess et al., 1997). Lethargic mice display ataxia, lethargic behaviours and focal motor seizures a similar phenotype to that associated with... 

Burgess DL, Jones JM, Meisler MH, Noebels JL (1997) Mutation of the Ca2+ channel beta subunit gene Cchb4 is associated with ataxia and seizures in the lethargic (lh) mouse. Cell 88 385—392. 

McEnery MW, Copeland TD, Vance CL (1998) Altered expression and assembly of N-type calcium channel alphalB and beta subunits in epileptic lethargic (lh/lh) mouse. J Biol Chem 273 21435-21438. 

A 9-day-old mouse sleeps for more than 24 h after an intracranial injection of 70 pg of the peptide per gram body weight. Under the same conditions, a 22-day-old mouse becomes lethargic at about 10 min after injection and sleeps for 3 h. 

The lethal effects of TSST-1 and HI35A, potentiated by LPS (75 pg/mouse), was tested in BALB/c mice. TSST-1 doses of 10, 1.0, 0.1, or 0.01 pg/mouse (n=15 per dose) were 73%, 53%, 33%, and 0% lethal, respectively. The calculated LD50 of TSST-1 was 47.2 pg/kg (0.94 pg/mouse). In contrast, a HI35A dose of 10 pg per mouse (500 pg/kg) was not lethal (n=15). Controls injected with either TSST-1 or HI35A alone (10 pg/mouse) did not show any adverse reactions, but animals given only LPS (75 pg/mouse) had ruffled fur and were lethargic. None of the control mice died. 

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