Piamadre (brain): structure and functions of this layer of the meninges

When we talk about the human nervous system, which includes the brain, we often forget that this set of anatomical structures could not function well without many other parts of the body associated with it. Specifically, our brain and spinal cord depend on the protection of a number of protective layers called the meninges.

In this article we will see as one of those layers of the meninges, the so-called piamadre, And what functions it performs in our body. But first, let’s briefly review what exactly the meninges are.

    Meninges: definition

    The meninges are a series of tissues that line the central nervous system, providing both protection and support for the circulatory system to deliver blood to many areas occupied by neurons and glial cells.

    Also, as we will see, the brains too they are used to produce cerebrospinal fluid, Which fills several spaces of the central nervous system and also performs a function of protecting and supporting that part of the body (for example, by leaving a space between the brain and the hard parts with which it can collide).

    In contrast, the meninges are not a homogeneous structure, but are divided into several layers, each with its own properties and with a different consistency. They consist of three membranes, placed one on top of the other. It is, from top to bottom, from dura mater, arachnoid and piamater.

      What is piamadre?

      As we have seen, the piamater is the deepest layer of the meninges, which means that it is the one that is furthest from the bones of the skull and scalp.

      On another side, the piamater is very fine and has the consistency of a flexible mesh, Which means, for example, that the furrows and fissures of the cerebral cortex which covers it are insinuated on its surface.

      This is because it creates a suitable way for the ducts that carry blood to the cells of the brain and spinal cord to pass through it. In addition, being so thin, it can adhere well to the contour of the brain.

        type

        It is possible to differentiate two types of piamater: the cranial and the spine.

        spinal cord

        The spinal cord is responsible for wrapping the entire spinal cord from top to bottom.

        Skull pajamas

        Although its composition is almost identical to that above, its functions are better suited to the morphological characteristics of the brain.

        functions

        Among the main functions of the piamater are the following.

        1. Irrigation of the nervous system

        The piamater is responsible for providing physical support to the veins, arteries and capillaries that pass from the outside environment to supply the tissues of the central nervous system. Thus, their presence of neurons and glial cells can survive thanks to the combination of oxygen and nutrients that reach them through the blood.

        2. Production of cerebrospinal fluid

        From the motherfucker choroidal tissue emerges, Which in turn germinate the choroid plexuses, places where cerebrospinal fluid is secreted.

          3. A mold for the spinal cord

          The consistency and shape of the spinal cord make it this anatomical structure tends to deform. However, the piamadre helps prevent this from happening, as it is responsible for whatever is in place and at the same time its mold function also prevents it from lying down under the effect of the gravity.

          4. Create a filter

          Like the blood-brain barrier, piamadre also serves to prevent certain unwanted particles and substances from coming into contact with neurons and glial cells in the central nervous system. But this protection is more quantitative than qualitative, Since by itself the piamater does not block perfectly the passage of the concrete elements, but limits the diffusion of these.

            5. It leaves a space between the circulatory system and the nervous system

            The piamadre is permeable, but at the same time dense enough to create a separation between the nervous system and blood vessels. This allows certain proteins and particles to cross between the two media, moving up or down to or from the subarachnoid space.

            6. Sensory function associated with pain

            The central nervous system does not have pain sensors (nociceptors), but the piamater is in contact with them. it makes that certain accidents such as herniated discs cause painLet us know that there is something in our body that is not working properly.

              associated disorders

              The main diseases that affect the piamater are those that eventually lead to inflammation, which in this case it’s called meningitis. This health problem associated with piamater and arachnoids can be caused by certain bacteria, viruses and fungi, sometimes after sustaining an injury in the area.

              On the other hand, arachnoid and piamater and duramater can be the place where blockage of blood vessels occurs, causing ischemic attacks and aneurysms of varying severity.

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