Spermine NONOate is a diazeniumdiolate nitric oxide donor [1].

Nitric oxide (NO) increases intracellular guanosine 3' 5' cyclic monophosphate and activates guanylate cyclase, which then cause relaxation of vascular smooth muscle [1].

Spermine NONOate is a diazeniumdiolate nitric oxide donor. In rat pulmonary artery rings, spermine NONOate (100 μM) increased guanosine 3'5' cyclic monophosphate (cyclic GMP) by 35 fold and caused cyclic GMP-independent relaxation by activation of sarco-endoplasmic reticulum Ca2+-ATPase, Na+/K+-ATPase and calcium-activated potassium channels [1]. Spermine NONOate inhibited human low-density lipoprotein (LDL) oxidation induced by the copper(II) sulfate [2].

In rats with bilateral uterine horn injury, spermine NONOate (1 mg) inhibited the formation of adhesions. Also, The N,O-carboxymethylchitosan (NOCC) plus spermine NONOate group had a lower severity score and extent score than the spermine NONOate group. These results suggested that spermine NONOate reduced the postoperative adhesions [3].

References:
[1].  Homer KL, Wanstall JC. Cyclic GMP-independent relaxation of rat pulmonary artery by spermine NONOate, a diazeniumdiolate nitric oxide donor. Br J Pharmacol, 2000, 131(4): 673-682.
[2].  Goss SP, Hogg N, Kalyanaraman B. The antioxidant effect of spermine NONOate in human low-density lipoprotein. Chem Res Toxicol, 1995, 8(5): 800-806.
[3].  Duran B, Ak D, Cetin A, et al. Reduction of postoperative adhesions by N,O-carboxymethylchitosan and spermine NONOate in rats. Exp Anim, 2003, 52(4): 267-272.