Table 3.

Basal NOS activity in age-matched control and STZ-induced diabetic rats

Duration of diabetes	Age-matched controls	STZ-induced diabetes
1–2 weeks	8.44 (CI:4.52–15.75) (n = 7)	6.39 (CI:3.42–11.93) (n = 7)
8–10 weeks	4.84 (CI:2.41–9.73) (n = 6)	11.57 (CI:7.46–17.95)*† (n = 12)
18–20 weeks	2.04 (CI:1.36–3.04)** (n = 14)	3.60 (CI:1.90–6.82)(n = 7)

Basal NOS activity in age-matched controls decreased with maturation (P = 4.101 × 10⁻⁵, analysis for linear trend). In STZ-induced diabetics, basal NOS activity was biphasic (P = 3.996 × 10⁻⁴, one-way ANOVA),first increasing to twice age-matched control levels at 8–10 weeks, then decreasing back to age-matched control levels at 18–20 weeks. The increase in NOS activity may be a compensatory mechanism to counteract the simultaneous impairment of NO–cGMP pathway responsiveness. The data are given as means and 95% confidence intervals (CI).

^*P < 0.05

^**P < 0.005 compared to 1–2 weeks in same group.

^†P < 0.05 compared to age-matched controls.