Despite their different locations, structural organisations and associations with very different accessory cells, the Lansoprazole sensory endings of muscle spindles and the lanceolate endings of hair follicles share some fundamentally important properties in common, together with other cutaneous, joint and muscle afferents, and some visceral afferents such as baroreceptors. Thus, all of these are lowthreshold mechanoreceptors, responding to low force stimuli, often of minute amplitude; and all are formed of the peripheral sensory terminals of primary afferent axons whose cell bodies are located in the dorsal-root or cranial nerve ganglia. They also share in common the fact that the molecular basis of their mechanosensitivity is unknown. In some cases, such as the muscle spindle, classical neurophysiology has provided us with very detailed input:output properties where the inputs are well-defined and precisely controlled mechanical stimuli, and the outputs are the resulting spike trains in the afferent axons. In such experiments the overall process of mechanosensory transduction is treated as a black box, whose transfer function can, at least in principle, be determined from the I/O properties alone. This treatment is very useful in bioengineering, but it is clearly unsatisfactory for our understanding of a fundamentally important biophysical process. For that we need to see inside the ��black box��. Much of our recent work has centred on the role of a glutamatergic system mediated by SLVs in mechanosensory terminals. The rate of SLV turnover is activity dependent, and experimental manipulation of the system alters the sensory ending��s I/O properties, at least of the muscle spindle, so it is feasible that the system is part of an automatic gain control of the mechanosensory black box, operating with a time course of seconds to minutes. We encountered the importance of Ca2+activated K + channels, both SK and BK, in the course of investigating the possible role of voltage-gated Ca2+ channels in SLV L-Glutamine recycling in muscle spindles.SLV recycling is a Ca2+dependent process, so we were surprised initially to find that blocking P/Q Ca2+ channels enhanced rather than inhibited muscle-spindle sensory responses to stretch; however, as P/Q channels are frequently associated with KCa channels, we also tried blocking SK and BK channels and found that blocking either or both types produced similar effects to P/Q blockage.