Thyroid autoimmunity in children with coexisting type 1 diabetes mellitus and celiac disease: a multicenter study.

BACKGROUND: Children with type 1 diabetes mellitus (DM1) are more prone to developing thyroid autoimmunity (TAI); TAI also occurs more frequently in patients with celiac disease (CD). AIM: To determine whether TAI occurs more frequently in children with coexisting DM1 and CD compared to children with DM1 only, and whether the clinical course of DM1 is influenced by concomitant TAI. PATIENTS AND METHODS: We performed a multicenter retrospective case-control study comparing data from 84 diabetic children with CD (group 1) to 167 diabetic children without CD (group 2), matched by age at DM1 onset, duration of DM1 and center. Markers of TAI, thyroid function and HbA1c were recorded. The TAI follow-up lasted 4.9 +/- 2.8 years. RESULTS: TAI was diagnosed in 13% of children in group 1 and 19% of children in group 2 (ns). Diabetes control was not influenced by TAI in either group. CONCLUSIONS: Occurrence of TAI in diabetic children is not related to coexisting CD. TAI does not lead to worsening of metabolic control in children with DM1.

Inhibition of the NANC relaxation of the guinea-pig proximal colon longitudinal muscle by the purinoceptor antagonist PPADS, inhibition of nitric oxide synthase, but not by a PACAP/VIP antagonist.

The effects of the P(2)-purinoceptor antagonist pyridoxal-phosphate-6-azophenyl- 2('),4(')- disulphonic acid (PPADS), the nitric oxide (NO) synthase inhibitor N(G)-nitro- l -arginine (l -NOARG), the K(+)-channel blocker apamin, the pituitary adenylate cyclase activating peptide (PACAP) antagonist PACAP(6-38) and the sensory neuron-blocking drug capsaicin were examined on the non-adrenergic, non-cholinergic (NANC) relaxation evoked by electrical field stimulation in the longitudinal muscle of the guinea-pig proximal colon. Both PPADS (50 microm) and l -NOARG (100 microm) significantly inhibited the NANC relaxation. In the presence of l -NOARG, PPADS inhibited and apamin (100 nm) practically abolished the response. Capsaicin slightly but significantly enhanced the NANC relaxation at 10, but not at 1 Hz stimulation frequency. PACAP(6-38) (3 microm) had no effect on the NANC relaxation, although it abolished the relaxant effect of exogenous PACAP(1-27) (10 nm) and reduced that of exogenous vasoactive intestinal polypeptide (VIP, 30-100 nm) by about 60 %. PPADS (50 microm) inhibited the relaxant action of exogenous adenosine 5(')-triphosphate (ATP; 1 and 10 microm), the inhibition being stronger at 1 microm ATP. These data indicate that an exogenous P(2)-purinoceptor stimulant (possibly ATP) and NO are involved in the NANC relaxation of the guinea-pig colon. The 'non-nitrergic' apamin-sensitive component of the response might also include an unidentified transmitter. No evidence has been found for a mediating role of PACAP/VIP-like peptides.