Peripheral 5-HT _1A and 5-HT ₇ Serotonergic Receptors Modulate Parasympathetic Neurotransmission in Long-Term Diabetic Rats

Figure 8

Changes in heart rate (ΔHR) evoked by exogenous administration of 1, 5, and 10 μg/kg acetylcholine in atenolol (1 mg/kg) pretreated in long-term diabetic pithed rats after i.v. administration of a bolus of 1 mL/kg of saline solution, 5-hydroxytryptamine (5-HT, 10 and 100 μg/kg; 𝑛=10), 5-carboxamidotryptamine (5-CT 10 and 100 μg/kg; 𝑛=10), or 8-hydroxydipropylaminotretalin hydrobromide (8-OH-DPAT 50 μg/kg; 𝑛=5). *𝑃<.05 compared with saline.