Rauch D, Sparwasser C, Drescher P, Knes J M, Madsen P O
Department of Surgery, University of Wisconsin, Madison 53705, USA.
Invest Radiol. 1997 Jul;32(7):424-8. doi: 10.1097/00004424-199707000-00009.
Changes in contractility of corpus cavernosum (CC) smooth muscle caused by radio contrast medium may result in misinterpretations of cavernosography used diagnostically in erectile dysfunction.
The authors investigated the direct effect of various contrast media on rabbit CC smooth muscle tissue strips in an in vitro model by adding contrast medium to the tissue in a perfusion bath and recording the resulting contractions. Glucose addition was used as control.
Application of high-osmolar, ionic contrast medium diatrizoate-induced CC smooth muscle contractions of 57% of the control potassium chloride (124 mM) induced contractions. The low-osmolar (862 mOsm/kg) nonionic monomer contrast medium, iohexol, and the iso-osmolar (300 mOsm/kg) nonionic-dimer contrast medium, iodixanol, elicited contractions of 34% and 36% of the potassium chloride control contractions, respectively. High- and Iso-osmolar glucose solutions caused contractions of 51%, 38%, and 24% of the control, respectively. Cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) regulate CC smooth muscle contractions. These are influenced by different drugs including phosphodiesterases (PDEs), forskolin, and 3-morpholinsydnonimine hydrochloride (SIN-1). The nonspecific PDE inhibitors papaverine (0.1 mM) and theophylline (1 mM) reduced the contrast medium-induced contractions to 66% and 69%, respectively. The specific PDE inhibitor milrinone (0.1 mM) reduced the contractions to 69%; 0.1 mM forskolin and SIN-1 reduced the contractions to 34% and 41%, respectively.
Contrast medium induces CC smooth muscle contractions, depending mainly on the osmolality of the solution. The contractions are reduced but not abolished by elevating the intracellular cAMP and cGMP concentrations. The clinical applications in cavernosography are discussed.
放射造影剂引起的海绵体（CC）平滑肌收缩性变化可能导致在勃起功能障碍诊断中使用的海绵体造影出现误诊。
作者通过在灌注浴中将造影剂添加到组织中并记录由此产生的收缩，在体外模型中研究了各种造影剂对兔CC平滑肌组织条的直接影响。添加葡萄糖作为对照。
高渗离子造影剂泛影葡胺引起的CC平滑肌收缩为对照氯化钾（124 mM）诱导收缩的57%。低渗（862 mOsm/kg）非离子单体造影剂碘海醇和等渗（300 mOsm/kg）非离子二聚体造影剂碘克沙醇分别引起氯化钾对照收缩的34%和36%的收缩。高渗和等渗葡萄糖溶液分别引起对照收缩的51%、38%和24%的收缩。环磷酸腺苷（cAMP）和环磷酸鸟苷（cGMP）调节CC平滑肌收缩。这些受到包括磷酸二酯酶（PDEs）、福斯可林和盐酸3-吗啉代 sydnonimine（SIN-1）在内的不同药物的影响。非特异性PDE抑制剂罂粟碱（0.1 mM）和茶碱（1 mM）分别将造影剂诱导的收缩降低至66%和69%。特异性PDE抑制剂米力农（0.1 mM）将收缩降低至69%；0.1 mM福斯可林和SIN-1分别将收缩降低至34%和41%。
造影剂诱导CC平滑肌收缩，主要取决于溶液的渗透压。通过提高细胞内cAMP和cGMP浓度，收缩减少但未消除。讨论了其在海绵体造影中的临床应用。
