*3.3.3 Other roles of EOPs*

EOP (including β-EP) also performs other functions, and one of these is transferring the body into hypobiosis, or the maximum energy-saving mode. It is characterized by heart and respiration rate decreases, changes in blood pressure, and temperature decline [144]. It turns out that hypobiosis is caused not so much by the depletion of the other two regulatory systems (SAM and HPA axis), via activation of the EOS. The shock (state of exhaustion) is an extreme degree of the stress response, in which the EOS has a very important role. Recently, it has been shown that a natural mechanism for recovering from abimal shock has "small peptides", or metabolic substances originating from the EOS, for example, the FMRFamide-related peptides (FaRPs) [157, 158]. These metabolic substances from endogenous opioids have an effect that is the opposite to them (supporting autoregulatory negative feedback). The first thing that happens during stress is the depletion of the adrenal apparatus. To return to its normal state, it must be activated in some way. FaRPs through binding of β-adrenergic receptors perform this function, thus bringing the body out of a state of exhaustion. This indicates that self-healing of stress (natural sanogenesis) is particularly associated with this peptide origin from the EOS.
