按傳出神經(jīng)末梢釋放的遞質(zhì)不同,可將傳出神經(jīng)分為兩大類。
1.膽堿能神經(jīng)當(dāng)神經(jīng)興奮時(shí),其末梢主要釋放乙酰膽堿稱為膽堿能神經(jīng)。它包括:①全部交感神經(jīng)和副交感神經(jīng)的節(jié)前纖維;
②副交感神經(jīng)的節(jié)后纖維;
③極少數(shù)交感神經(jīng)的節(jié)后纖維,如支配汗腺分泌和骨骼肌血管舒張的交感神經(jīng);
④運(yùn)動(dòng)神經(jīng)。此外,腎上腺髓質(zhì)受交感神經(jīng)支配,但此神經(jīng)屬膽堿能神經(jīng),興奮時(shí)末梢釋放乙酰膽堿,促使腎上腺髓質(zhì)釋放腎上腺素和少量去甲腎上腺素。
2.去甲腎上腺素能神經(jīng)當(dāng)神經(jīng)興奮時(shí),其末梢主要釋放去甲腎上腺素稱為去甲腎上腺素能神經(jīng)。大多數(shù)交感神經(jīng)節(jié)后纖維均屬此類神經(jīng)。
1.膽堿能神經(jīng)當(dāng)神經(jīng)興奮時(shí),其末梢主要釋放乙酰膽堿稱為膽堿能神經(jīng)。它包括:①全部交感神經(jīng)和副交感神經(jīng)的節(jié)前纖維;
②副交感神經(jīng)的節(jié)后纖維;
③極少數(shù)交感神經(jīng)的節(jié)后纖維,如支配汗腺分泌和骨骼肌血管舒張的交感神經(jīng);
④運(yùn)動(dòng)神經(jīng)。此外,腎上腺髓質(zhì)受交感神經(jīng)支配,但此神經(jīng)屬膽堿能神經(jīng),興奮時(shí)末梢釋放乙酰膽堿,促使腎上腺髓質(zhì)釋放腎上腺素和少量去甲腎上腺素。
2.去甲腎上腺素能神經(jīng)當(dāng)神經(jīng)興奮時(shí),其末梢主要釋放去甲腎上腺素稱為去甲腎上腺素能神經(jīng)。大多數(shù)交感神經(jīng)節(jié)后纖維均屬此類神經(jīng)。