<prompt> Translate the following text to SwahiliNatural erections are elicited by the neural signaling of nitric acid, which in turn is triggered by some desire, or thought, or external stimuli.  <response>: Urembo wa kawaida huchochewa na ishara ya neva ya asidi nitriki, ambayo kwa upande wake huchochewa na tamaa fulani, au mawazo, au vichocheo vya nje. 