ple asant . ▁However ▁at ▁the ▁conclusion ▁of ▁prolong ed ▁an a est hes ia ▁patients ▁could ▁suffer ▁a ▁sudden ▁decrease ▁in ▁blood ▁pressure , ▁potentially ▁leading ▁to ▁card iac ▁d ys rh ythm ia ; ▁a ▁reaction ▁known ▁as ▁" cyc lo prop ane ▁shock ". ▁For ▁this ▁reason , ▁as ▁well ▁as ▁its ▁high ▁cost ▁and ▁its ▁explos ive ▁nature , ▁it ▁was ▁latter ly ▁used ▁only ▁for ▁the ▁induction ▁of ▁an a est hes ia , ▁and ▁has ▁not ▁been ▁available ▁for ▁clin ical ▁use ▁since ▁the ▁mid ▁ 1 9 8 0 s . ▁C yl ind ers ▁and ▁flow ▁meters ▁were ▁col oured ▁orange . ▁ ▁Ph arm ac ology ▁Cy clo prop ane ▁is ▁in active ▁at ▁the ▁G AB AA ▁and ▁g ly c ine ▁re cept ors , ▁and ▁instead ▁acts ▁as ▁an ▁N MD A ▁re ceptor ▁ant agon ist . ▁It ▁also ▁in hib its ▁the ▁A MP A ▁re ceptor ▁and ▁nic ot in ic ▁ac et yl ch oline ▁re cept ors , ▁and ▁activ ates ▁certain ▁K 2 P ▁channels . ▁ ▁Str ucture ▁and ▁bond ing ▁ ▁The ▁tri angular ▁structure ▁of ▁cy clo prop ane ▁requires ▁the ▁bond ▁angles ▁ ▁between ▁carbon - car bon ▁c oval ent ▁b onds ▁to ▁be ▁ 6 0 ° . ▁This ▁is ▁far ▁less ▁than ▁the ▁therm od ynam ically ▁most ▁stable ▁angle ▁of ▁ 1 0 9 . 5 ° ▁( for ▁b onds ▁between ▁atoms ▁with ▁sp 3 ▁hy