Table 1.

Sex differences in the 6-hydroxydopamine (6-OHDA) model of Parkinson’s disease.

MFB injection	Striatal DA content % lesioned versus unlesioned side		TH-IR cells % lesioned versus unlesioned side cells
	Male	Female	Male	Female
Vehice control	105.4 ± 9.8	100.3 ± 6.2	101.4 ± 8.9	98.6 ± 8.5
1 μg 6-OHDA	50.3 ± 4.8⁎	72.7 ± 6.7⁎,#	59.3 ± 4.5⁎	76.2 ± 2.5#
6 μg 6-OHDA	4.2 ± 0.3⁎⁎	5.1 ± 0.3⁎⁎	25.5 ± 8.3	15.7 ± 6.1

Male rats and female rats at proestrus received a 4 μL injection into the left medial forebrain bundle of either vehicle or a dose of 6-OHDA (1 μg or 6 μg) under general anaesthesia. Two weeks later striatal tissue was collected for assessment of dopamine levels using high performance liquid chromatography coupled with electrochemical detection; the hindbrains were also dissected and processed immunocytochemically for tyrosine hydroxylase (TH), the rate-limiting enzyme in dopamine synthesis, as a marker of dopaminergic neurons, which were then counted. The left (lesioned) and right (unlesioned, control) striata and SNc were processed separately. Group means for the lesioned and unlesioned sides were used to calculate the percentage survival of TH immunoreactive (IR) cells. 6-OHDA reduced striata DA levels and TH-IR cell numbers in the SNc in a dose-dependent manner and a sex difference in the severity of the lesion was observed with the dose of 1 μg 6-OHDA. Values represent the mean ± s.e.m. (n = 6). Full details in Murray et al. (2003).

^⁎P < 0.05 for the effect of 6-OHDA versus vehicle.

^⁎⁎P < 0.01 for the effect of 6-OHDA versus vehicle.

^#p < 0.05 compared with males.