Pituitary Analogue in the Octopus

  title={Pituitary Analogue in the Octopus},
  author={M. J. Wells and John Wells},
THE optic glands of Octopus vulgaris lie on either side of the central part of the supraoesophageal brain, on the stalks of the optic lobes (Fig. 1): they control hormonally the onset of sexual maturity in female octopuses1. Production of hormone is regulated by an inhibitory nerve supply from the subpedunculate lobe. This in turn is probably affected by daylength, for section of optic nerves causes precocious sexual maturity in octopuses1, and a period of artificially reduced daylength can… Expand
Optic glands and the state of the testis in Octopus
If the optic glands are removed from mature male octopuses, the weight of the testis and its ducts decline. Spermatophore production eventually ceases after five or six weeks. The effect of theExpand
Innervation of the Cephalopod Optic Gland
The optic glands of cephalopods are endocrine organs secreting a gonadotropic hormone under the control of the brain and this inhibition is mediated by a complex neural pathway from the retina to the subpedunculate lobe of thebrain and thence to the optic gland itself. Expand
The subpedunculate lobe of the octopus brain: evidence for dual function.
Two nerves arise from the subpedunculate lobe of the octopus brain and appear to be involved in growth and/or maturation and the axo-axonal synapse is supposed to inhibit the axiomatic synapse in immature glands. Expand
Reproduction versus somatic growth: hormonal control in Octopus vulgaris.
Octopus vulgaris can be forced into precocious maturity by removal of the subpedunculate lobe from the brain, an operation that releases the optic glands from inhibition, and allows them to secrete a gonadotropin, which increases the release of amino acids from muscle. Expand
Octopus Gonadotrophin‐Releasing Hormone: A Multifunctional Peptide in the Endocrine and Nervous Systems of the Cephalopod
The results suggest that oct‐GnRH induces the gonadal maturation and oviposition by regulating sex steroidogenesis and a series of egg‐laying behaviours via the oct‐gnRH receptor. Expand
Hormonal Inhibition of Feeding and Death in Octopus: Control by Optic Gland Secretion
Female Octopus hummelincki lays eggs, broods them, reduces its food intake, and dies after the young hatch. Removal of both optic glands after spawning results in cessation of broodiness, resumptionExpand
A study on the optic glands of Sepioteuthis lessoniana from the Red Sea
In the present work the optical glands of the reef squid Lessoniana lessoniana were are found in young and adult individuals. They are paired small elongated organs that lie at the aboral end of theExpand
Endocrinology of reproduction in molluscs
Among molluscs the optic glands of the cephalopods and the dorsal bodies of the gastropods are endocrine organs which are involved in the regulation of reproductive processes and some indications that the optic tentacles play a part in regulating reproduction are shown. Expand
Ultrastructure of the optic gland of the squid Sepiotheutis sepioidea (Cephalopoda: Loliginidae)
The fine structure of the optic gland (OG) in the tropical squid Sepiotheutis sepioidea at different sexual maturity stages is described and secretory cell nucleus length and organelle abundance showed oseillations associated with the life cycJe. Expand
Sexual displays and mating of Octopus vulgaris Cuvier and O. cyanea Gray and attempts to alter performance by manipulating the glandular condition of the animals.
The sequence of events preceding copulation in aquaria is described for each species and the mechanism of spermatophore transfer is discussed in some detail, with no effect on sexual behaviour. Expand


It is concluded that maturation of the gonad is determined by secretion from the optic glands which is normally held in check by an inhibitory nerve supply from the subpedunculate/dorsal basal lobe area. Expand